Liquid fabric conditioning compositions are known in the art. Liquid fabric softening compositions containing a light-stable pink color are described by Wahl, U.S. Pat. No. 4,822,499. Softening compositions of a light-stable pink color are described by Wahl, U.S. Pat. No. 4,897,208. Dyes utilized in the '208 patent are oil-soluble and are said to be very difficult to incorporate. Piper et al., U.S. Pat. No. 4,844,820 discloses liquid softening compositions of a light unstable pink color, the compositions requiring protective packaging to protect them from light. Coffindafer, U.S. Pat. No. 4,863,620 discloses a liquid fabric conditioning composition having a pH of less than 6 and containing specific yellow and blue colorants which provide a yellow color in the composition and which upon dilution and increase of pH to about 7.5 turn blue.
Red dyes described herein have not been previously disclosed for use in fabric softening compositions. The '499 patent discloses four light stable dyes that produce pink shades. However, the present invention offers additional dyes that produce aesthetically pleasing pink colors, enabling the practitioner to choose from a greater variety of light-stable dyes for preparation of pink-colored liquid fabric softeners.
It is very difficult to find dyes that on addition to a liquid conditioning product result in an aesthetically pleasing pink-colored product. Many red dyes provide pink shades but are unacceptable to a consumer because of potential toxicity or, if safe, because they produce undesirable shades. Other red dyes provide pink color but are unstable on storage or fade upon exposure to light.